Organic light emitting diode (OLED) units are organic thin film electroluminescent devices, where OLED display panels possess many outstanding properties such as a simple preparation process, low cost, high electroluminescent efficiency, amenability to forming flexible structures, wide view angles, etc. Therefore, display technologies that use organic light-emitting diodes have become important display technologies.
Compared with thin film transistor-liquid crystal display (TFT-LCD) of existing flat panel display technologies, active-matrix organic light emitting diodes (AMOLED) possess many outstanding properties such as a high contrast ratio, wide view angles, low power consumption, lighter in weight, thinner, etc. AMOLEDs are expected to be next-generation flat panel display technology after LCDs, and AMOLEDs are one of the most anticipated technologies among current flat panel display technologies.
As shown in FIG. 1, during manufacture of back anodes 11 of conventional top-emitting AMOLEDs, structures of the top metal layers 113/silvers 112/bottom metal layers 111 are employed. The silver 112 is used for forming a transmitting layer. The top metal layer 113 and the bottom metal layer 111 employ the same film-forming parameters in the physical vapor-phase film forming processes. The etching process of the anode 11 is divided into three processes: etching of a top electrode, etching of a silver, and etching of a bottom metal layer when performing wet etching on the anodes 11. Because the top metal layer 113 is etched again during the etching of the bottom metal layer, it causes a huge loss of the top metal layer 113. It leads to the deposit of organic light-emitting materials 12 of OLEDs, which is deposited via vapor deposition afterwards, falls on the top of the silver 112 and influences light emitting of the OLEDs.